ghc 9.4.3 panic with funResultTy

Summary

I mentioned this as part of #22171 (closed) but now that 9.4.3 has been released I wanted to make sure it's not lost.

Trying to compile the swish package results in

Building library for swish-0.10.2.0..
[ 1 of 55] Compiling Data.Interned.URI
[ 2 of 55] Compiling Data.Ord.Partial
[ 3 of 55] Compiling Data.String.ShowLines
[ 4 of 55] Compiling Network.URI.Ord
[ 5 of 55] Compiling Swish.GraphClass
[ 6 of 55] Compiling Swish.GraphMatch

<no location info>: error:
    panic! (the 'impossible' happened)
  GHC version 9.4.3:
	funResultTy
  GenLabelMap lb_adso LabelIndex
  Call stack:
      CallStack (from HasCallStack):
        callStackDoc, called at compiler/GHC/Utils/Panic.hs:182:37 in ghc:GHC.Utils.Panic
        pprPanic, called at compiler/GHC/Core/Type.hs:1334:49 in ghc:GHC.Core.Type

Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug

Steps to reproduce

With GHC 9.4.3 (thanks ghcup)

% ghc --version
The Glorious Glasgow Haskell Compilation System, version 9.4.3

we have

% git checkout https://gitlab.com/dburke/swish
% cd swish
% cabal install --allow-newer=base
Wrote tarball sdist to
/home/dburke/haskell/ghcup/swish/dist-newstyle/sdist/swish-0.10.2.0.tar.gz
Resolving dependencies...
Build profile: -w ghc-9.4.3 -O1
In order, the following will be built (use -v for more details):
 - swish-0.10.2.0 (lib) (requires build)
 - swish-0.10.2.0 (exe:Swish) (requires build)
Starting     swish-0.10.2.0 (lib)
Building     swish-0.10.2.0 (lib)

Failed to build swish-0.10.2.0.
Build log (
/home/dburke/.cabal/logs/ghc-9.4.3/swish-0.10.2.0-e3487166464e6bbde8ec07c43b2587c3fef0f74f131cda10f70441643557d8ef.log
):
Configuring library for swish-0.10.2.0..
Preprocessing library for swish-0.10.2.0..
Building library for swish-0.10.2.0..
[ 1 of 55] Compiling Data.Interned.URI
[ 2 of 55] Compiling Data.Ord.Partial
[ 3 of 55] Compiling Data.String.ShowLines
[ 4 of 55] Compiling Network.URI.Ord
[ 5 of 55] Compiling Swish.GraphClass
[ 6 of 55] Compiling Swish.GraphMatch

<no location info>: error:
    panic! (the 'impossible' happened)
  GHC version 9.4.3:
	funResultTy
  GenLabelMap lb_adso LabelIndex
  Call stack:
      CallStack (from HasCallStack):
        callStackDoc, called at compiler/GHC/Utils/Panic.hs:182:37 in ghc:GHC.Utils.Panic
        pprPanic, called at compiler/GHC/Core/Type.hs:1334:49 in ghc:GHC.Core.Type

Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug

[ 8 of 55] Compiling Swish.GraphPartition
[ 9 of 55] Compiling Swish.QName
...
... a lot of other stuff that's not relevant here
...

Expected behavior

To be able to build and test the code

Environment

• GHC version used: 9.4.3

Optional:

• Operating System: Linux
• System Architecture: x86_64